Drying apparatus



E. D. SPIERER DRYING APPARATUS Aug. 5, 1952 3 Sheets-Sheet 1- Filed June 11, 1951 INVENTOR. Jdu/ard 17 S w'erer 1 2 E. D SPIERER 2,606,274

DRYING APPARATUS 5 Sheets-Sheet 2 INVENTOR. Edward J S a'emr wink/V5) Aug. 5, 1952 Filed June 11, 1951 E. D. SPIERER DRYING APPARATUS Aug. 5, 1952 5 Sheets-Sheet 5 Filed June 11, 1951 INVHVTOR. idmajd] S' azjerer Patented Aug. 5, 1952 DRYING APPARATUS Edward D. Spierer, Brooklyn, N. Y., asslgnor to Edi Holding, Inc., Brooklyn, N. Y., a corporation of New York Application June 11, 1951, Serial No. 230,978

4 Claims. (01. 219-39) The present invention relates to apparatus for drying objects, such as the hands of a user, and more particularly to such apparatus, which may be used at any place where a conventional source of electric power is available without the necessity of providing heavier power leads and other power supply facilities capable of providing higher amperage power than is available in the conventional electric outlets available in homes and business establishments and wherein, for example, the outlet may be protected by a fuse of a relatively low value, such as 15 amperes.

It has been customary in the past to provide hand drying apparatus wherein there is included a blower, usually operated by an electric motor, and wherein an electric heating means is provided on the downstream side of the blower for heating the air to a desired or predetermined temperature. In order that any substantial volume of air be heated very rapidly to a desired high temperature in such a device, the heat capacity and consequently the current consumption (amperage) for such a heating means must be quite high, often 40 to 50 amperes. Thus, when such a device is installed in a commercial establishment or in a home, it is necessary that there be a special power supply therefor, using very heavy wires so as to permit the safe passage of this high current. If such a power supply at high amperage is not available, it is, of course, necessary to provide it before the prior art devices, as above described, may be used. This may involve the reconstruction of a substantial portion of a building and be correspondingly and sometimes prohibitively expensive.

A primary general object of the present invention is to provide a device having a maxi-p mum power demand which will not overtax the conventional electric outlets available instores and oiiices, wherein the size of the wires and the fuses commonly associated therewith are such as to limit the safe current to a value not greater than about 15 amperes, for example.

Obviously, it is impossible with a low current demand as aforesaid, to provide for the instantaneous heating of the desired volume of air to the desired temperature by the use of aheating element on the downstream side of the blower as was conventional in the prior art. The present invention resorts, therefore, to provide a heat storage means, which comprises a body of material of relatively high heat capacity and of substantial size, to which heat may be slowly butsubstantiallycontinuously supplied at a rate much less than that required for th heatand ing elements of prior art drying devices aforesaid, and at a rate which can be accommodated by the current supply through a conventional resistance outlet aforesaid, i. e., not greater than a 15 ampere demand. Preferably, the heating means in accordance with the present invention consumes or has'a rating of not over about 10 amperes. Coupled with this heat storage means, means are provided in accordance with the present invention for abstracting heat from the heat storage means wherever the drying means is to be used and at a rate required by the drying means for heating the desired volume of air to the desired temperature, that is, at a rate much greater than at which heat is normally supplied to the heat storage means as aforesaid. In conjunction with the above there will, of course, b provided a more or less conventional blower driven by a more or less conventional driving means, such as an electric motor. There may also be provided in conjunction with the above, a means by which the air and the article to be dried, or both, are sterilized, for example, by rays from a sterilizing tube which are now conventional in the art. Such a tube not only generates rays which are themselves sterilizing in character, but also generates ozone, which may be used for deodorizing or otherwise sterilizing the vicinity. Provision is preferably made for operating this sterilizing tube either automatically, wherever the drying means is operated, or manually, by a manually controlled switch.

The drying apparatus of the present invention as has been outlined above, may be operated manually by a manually controlled switch, or automatically in response to the presence of an object to be dried in a drying zone, for example, by the interruption of a beam of light passing through this zone and the use of a photocell with a suitable control circuit.

Other and detailed features and embodiments of the present invention will become apparent from th following description thereof and will be pointed out in the appended claims, all when considered with the accompanying drawings, in which:

Figure 1 is a view in perspective of an apparatus, embodying the present invention;

Fig. 2 is a view substantially in transverse vertical section taken on the line 2-2 of Fig. 1 and showing the interior construction;

Fig. 3 is a view in transverse vertical section taken substantially on the line 33 of Fig. 2;

Fig. 4 is a wiring diagram, illustrating one type of circuit which may be used for controlling the apparatus shown in the preceding figures.

While apparatus embodying the present invention may be constructed in a large number of different forms, there is chosen for purposes of illustration in the accompanying drawings a hand drying apparatus, which has been tested on a commercial scale and found to be desirable in use. This apparatus is shown in its exterior contour in Fig. 1, and comprises a casing generally indicated at It, preferably of sheet metal or other suitable construction, and which may be mounted on any desired support, such as a wall of a room, by suitable means (not shown). The casing Ill has a generally inverted U-shaped contour, provid ing a recess I open to its underside, which may be considered a drying zone, and into which one or more objects to be dried may be introduced. The particular construction of the casing It) is not a critical part of the present invention, but is shown in Figs. 1, 2 and 3. This casing may be provided with several demountable and removable portions, which when open permit access into the interior for replacement or repair of the apparatus enclosed within the casing. For example, one end portion. shownat l2 may be removed from the main body portion of the casing by releasing a locking apparatus shown generally at [3, Fig. 2. A topporticn Id-may be similarly removed by releasing a locking means l5, access to which may be had once the end portion i2 is removed. There, is provided above the space or zone an open grill work l6, through which heated air is passed or blown onto an object to be dried which is located within the drying zone ii. Air may be admitted to the interior of the casing It in any suitable way, for example, through apertures formed in one or both ends of the casing IE3, or through suitable apertures formed in a manner not illustrated in the top portion l4 thereof. it is preferred, however, that the right hand end of the apparatus as seen in Fig. 2 be provided with apertures l! as shown in that figure in the form .of one or more Llouvered openings.

Suitably mounted within the casing Iii and preferably centrally thereof is a blower l8, which may be of any desired or conventional type and which may be operated by any suitable source of power, such as an electric motor IS. The blower I8 is arranged to supply air through an outlet opening or nozzle 20, Figs. 2 and 3, to a point centrally above a part of the grill it, so that the air thus blown downwardly by theblower l8 will impinge upon an object to be dried in the recess or drying zone H. centrally thereof and usually axial of the rotor of the blower, this inlet opening being indicated at 2| in Fig. 2.

In accordance with the present invention, there is provided a heat storage means, which may be continuously heated at a relatively slow rate and which is arranged to supply its heat at a relatively rapid rate to the air being moved by the blower l3. This heat storage means comprises a body 22 of material having a substantialand preferably relatively high heat capacity or specific heat. In this instance, the heat storage means preferably comprises a cast body of aluminum or an aluminum alloy. The heat storage means is of a substantial size, so as to have a large heat capacity, great enough to supply the heat required for the air for the drying of a'plurality of objects in rapid succession, so as to cope with such peak drying loads as may be met with The blower I8 has an inlet in the expected normal use of the apparatus. Associated with this heat storage means is a heating element shown at 23 and which may take any conventional form, preferably of a resistance type and preferably shielded, so that the heating element as a whole may be totally embedded in the body 22. As shown, the heating element 23 is doubled upon itself several times, so that a heating element several times as long as the body 22 may be used. In this case, the element 23 is bent three times, so that there will be substantially four times the length of heating element in respect to the length of the body 22. This particular ratio, however, is not critical.

Froma broadpoint of View, the electric heating element 23 used should be in good heat transferring relation to the body of material 22. The heating element 23 in accordance with the present invention has a heat capacity, for example, of 800 watts, which is substantially less in its demand for electric power than is safely available in the conventional,electriooutlets usually found in residences and in business buildings -.(15 amperes). As such, the heatingelement ,2;3-I n ay be operated continuously and also may be operated without at any time over-taxing the wiring or circuit in which it may l e-connected.

In a preferred form of the invention as shown in the accompanying drawings, the heating element 23 may be cast within the body of the material 22 b actin a a core he t e aterial 22 is as ou it th s way. he heatin e m t is tota m e de with n th heat storage means, so that all the heat generated therein w ll e sed in hat a l of i wi l b sup ed to t b o m ter a 2 In orde to m nim e st ay heat oss, the body of material 22 is preferably suitably surrounded y any es ed eat insulatin m ans s ow e erally at 24. Inasmuch as heat insulation has now become ahighly developed art, it is deemed unnecessary to give further details thereof except to state that some and preferablya considerable amount of heat insulation is preferably used in the practice ,of the present invention. This minimizes the operating cost ofthe apparatus by mini.- mizing heat losses therefrom which serve no useful purpose.

At the right end, as seen in Fig. 2, of the body of material 22, .there is provided an air inlet chamber 25 formed by top and side portions 2.6 of suitable heat insulating material and an end member' 21 preferably also of such: material. Access for air to the chamber 25 is had through the lower. end thereof,.which is open to the in-. terior of the casing H). The body of material 22 is further provided with an annular series of air passages 28, which are respectively parallel to the axis of the substantially cylindrical body 22 of the heat storage means. The passages 28 com-.

' municate with the chamber 25, at theirinletends at the right as is seen in Fig. 2, and with the inlet 2| of the blower at their left ends as seen in Fig. 2. Thus, there is provided a means for con-v ducting air from the atmosphere, which communicates through the apertures 11 with the inside of'the casing I0, and thence through the chamber 25, past the body of material 22 in which the heat is stored and in good heat transferring relation therewith by passing through the several passages 28, and thence to the intake 2| of the blower l8.

The. apparatus thus far described comprises all the essential elements of apparatus required for its complete operation, there being, of -course,

r V a suitable'electric circuit by which the heating element 23 may beenergized, preferably'on'a sub1 -*.tan tially continuous basis, and they meter: 9 driving a blower l 8 beirigienergized whenever. it is desired to dry'anobject. Many types of'electrical circuits are usable for this general purpose, a preferred circuitbeing that shown in Fig. sand including various automatic control devicesand various safety devices and also including a sterilizing tube,' which may be desired for use in a particular installation. g Before describing this particular circuit, however, it is to be understoodthat the present invention provides a devicewhich may, if desired, be operated manually, so thatthemotor l9 may be connected ina suitable circuit with a manually operated switch in a manner which will now be apparent to those skilled in the art for operating-the motor l9 whenever and as long as a user may desire. Such manual switch may be hand or foot operated, both systems being conventional in the art for controlling prior art types of drying apparatus as the present time.

As shown in Fig. 4, the apparatus of the present invention may be energized from any A. C. supply line, indicated by the leads 29 and 3B, the latter preferablybeing grounded as indicated at 3|. There is preferably included in the supply line a fuse device generally indicated at 32, which is adapted not only to open the circuit to the entire apparatus of the present invention whenever there is an electrical overload thereon as in the case of conventional fuses, but also is .adapted to respond to a too high temperature. Thus by locating the device 32 as shown in Fig. 2 adjacent to the heat storage body 22, whenever the temperature of that body and hence temperatures within the casing l0, tend to exceed some pre determined safe value, a-fusible element within the device 32 is adapted to melt to open the circuit, preventing further or substantial damage to any parts of the apparatus herein described.

There is also included in the line 29 a manually operated master switch 33, which may be located as shown at the lower right hand portion of Fig. 2, and operated by the proprietor of the premises in which the apparatus of the present invention is located. For example, this master switch may be made to operate only by a key, so that the apparatus as a whole may be deactivated under the control of the proprietor, who will be provided with sucha key; and operation by un: authorized persons will be prevented.

The heating element 23 may be connected from the grounded line 30 as shown in Fig. 4, through to a line 34, which is connected to the line 29 through the master switch 33 as shown. There may also be provided in series in the heating circuit a thermostatically operated switch 35, this switch including contacts 36 and a thermostatic element 31 positioned to be subject to the temperature of the heat storage body 22. In this way, the heating element 23 will be called upon to operate only when the heat storage means is at a temperature below some predetermined value to which the thermostatic switch is set; and. electric currentwill be saved once the heat storage means is brought up to the desired maximum temperature. Thus, the heating element 23 is, in a preferred form of the invention, adapted to operate continuously only when the temperature of'the heat storage means is below some predetermined value; 1 i a As shown, the motor I9 is connected to the grounded lead 33 and isalsoconnected through afline' 38iandla switch 39 to the line 34, which is normally [alive as shown whenever the master switch 33 is closed. .It is contemplated that a manually operated .switchmay be used in lieu of the switch 39,:iilthough the oircuit'shown in' Fig. 4 shows one form ofautomatic switch actuating means as hereinafter described.

There is preferably provided in conjunction with the apparatus of, theprese'ntinvention, but not as a necessary element thereof, a sterilizing tube 40, which'may be of a conventional commercial type, such as one manufactured and sold by the Westinghouse Company. This tube is preferably mounted as shown in Figs. 2 and 3 in' suitable sockets 4! adapted therefor and is energized by being connected across the secondary of a-transformer42, the primary of which is connected by a, lead 43 to the grounded line 30 and by a lead 44 through a. single pole, double throw switch 45, alternatively to the lead'38 or to a lead 45 which is connected to the lead 34. When the switch 45 .is in the position shown in full lines in the drawings, Fig. 4, the tube 40 will be operated intermittently and concomitantly with the motor l9. If, however, the switch 45 were moved to its oppositeposition as shown in dotted lines in Fig. 4, the tube 40 would be continuously energized as long as the master switch 33 is closed. This affords. an opportunity for a user to energize the tube 40 .for the generation of ozone to deodorize the vicinity'of the drying apparatus.

As aboveset iorth,',the apparatus of the present invention may be operated manually by a suitable manually operated switch. It may also be operated by various known automatic control means including those involving a change in capacitance of an electrical circuit due to the proximity of an object to be dried to some capacity-responsive element of the circuit. Further, it may beoperate'd as shown in Fig. 4 by the'use of a so-called "electrio eye," that is, by providing a beam of light passing across the drying zone and normally impinging upon a photocell. In such an arrangement, whenever an object to be dried, such as the hands of a user, are introduced in the drying zone, the beam of light is interrupted and the electrical characteristics of the circuit includingthe photocell thereby varied, so as to initiate the operation of a suitable control circuit.

" As shown in the accompanying drawings, there is provided a light source, which is energized from the secondary of a transformer 48, the primary of which is connected to'the current source bybeing connected respectively to the grounded lead 30 and to the lead 46 as shown.' There is also "provided a photocell 49 so positioned as normally to receive light from the light source 41. A suitable circuit of any desired kind including that herein particularly described may be employed for automatically controlling the switch 39 from'the photocell 49. For example, circuits as disclosed in either of my Patents Nos. 2,551,224 or 2,551,225, both granted on May 1, 1951, may be employed for this purpose.

There is shown in the accompanying drawings, however, a circuit embodying an electronic tube 50 of the cold cathode, gas-filled type'having internally thereof a cathode 5|, an anode 52, and a'starting electrode 53, and also provided externally thereof with an additional electrode'54.

; Such a tube and a circuit for use therewith is described in greater detail in my Patent'No.

2,551,225 aforesaid. 'Ifhe cathode-anode .Bircuit of thetube 5ll' is connected; across a part ofthe i a le A: y'jpo ent a 'fFor. tmsru pdsie, be.-v tween the leads f aud 34 there is provided a circuit in udin dm rin i olrpii nd a potential determin r gresistorffi inseries therewi h: h c h de'ifil V "is o necte to r un (the lead 30) by ajlead 1; "while the anode 152 is connected to apoint between the resistors J55 and'56 .by a lead 50' and a series-"connected coil 59 of a plate relay which is arranged mechanically to operate thefs witch 39. 'Asuitable holding oondenser 60 is shuntedacross the 001159215 shown, for'the purpose described in greater detail 'in my Patent No. 2,551,225 aforesaid V v Between the leads "Bland 58 .is a shunt circuit including series-connected resistors 61 and 62, the intermediate connection of which is connected by a lead 53 to the external electrode 54 of the tube '50. Thus, the external electrode will be energized by an; A. C. potentialin phase with the cathode-anode potential.

Also connected across the leads 34 and 30 is a circuit or current path including series-connected resistors 64, 6'5"and 66, the resistor 65 serving as a potentiometer resistor for a purpose hereinafter described, and a rectifier generally indicated at 61 being-- connected in series between the resistors 64 and 55-. in shunt with the resistors B5 and t6 is a condenser 68, which may be charged with polarities as "indicated on the drawings due to the tpresenceof the rectifier '61. The adjustable potentiometer tap-69 of the potentiometer resistor 65 is connected through a dropping resistor- Hlyto the cathode H of the photocell 49,'the anode 12 of which is connected to ground "(lead'30') by a lead '13. The cathode "II of the photocell 49 'is also connected through a resistor 14 with the 'starting electrode .53 of the tube 50.

In operation, itywill be seen'that the condenser 68 will be charged with the polarity indicated on the drawing, dueftothe presence of the rectifier 61,-and further that the starting electrode 53 will be supplied with a potential negative in respect to the cathode 51, also due to the connections shown and described. This negative potential will be varied by the photocell 40, sothat when the light from the source 4'! is impinging normally upon the photocelhthe potential effective on the startingelectrode53will be insuflioient to fire the tube 50, which will remain inactive as long as this situation exists. As airesult, the plate relay coil 5 9 wi 11 be deenergized and the switch When, however, the passage of, light from the source 41 to the photocell 49 :is interrupted, .the potential of the startingelectrode '53 will beincreased as explained in detail in my Patent'No,

2,551,225 aforesaid, ,so' as to cause the ionization of the gas in thetube SO between the starting electrode 53 and the Cathodeil. .Thisin turn will fire'th'e tube 50, permitting, current flow through the cathode-anode circuit thereof and energizing the relay coil ae soas to close the switch, 39'.' This'switch will be closed aslong as light to the photocell 4'9 continues to be interrupted. As a result; the motor 19 willibeoperated duringthis period'; 1and'in the position of the switch giiishowniiniull lines, the tube to will likewise foe -energized automatically during this period... Y I

Once the *light flowto the photocell 49 is again re-established by the removal from the drying zone 1| l "of;an"object"tobeg-dried, the potential ,on

the starting electrode 53.w ill a ain decrease; the tube 551 will cease firing; the relay coil v5 9 will be deenergized; and theswitch 39 will -'be,-op'en edby gravity or by any suitable means; such asa spring, conventional- 'in 'relay' apparatus of this kind; resulting in'the cessation of the operation of the motor 19 and the tube 40.

The purpoe of providing" the adjustable potentiometer 65%-59 isto providean adjustment as to sensitivitmy so as particularly to make the photocell sensitive to different amounts of light. Thisvmay be used to compensate for gradual re' duction-in the light emanating from any particular incandescent bulbused'as the'light source 41 and also to compensate for different light intensities coming'from diiferentbulbs, in the event that one should burn out and bereplaced by another giving a somewhat difierent amount of light.

As an example of the present'invention using the circuit shown in Fig,- "1, the following values of the circuit elements have been found to be operative, these values not being the only operative values however and being illustrative but not limiting. The heating element 23 may be an "800 watt Ca-lrgod unit made by General Electric Company. }The switch 35 may be a standard commercial thermostatic switch. The tube 50 maybe atube as particularly disclosed in my Patent No. 2,551,225 aforesaid. The -re'- sisters '55 and 5%; may have values oi-820 ohms and 10,000 ohms respectively. The "relay including coil 59 is a 2,500 ohm relay, *and the condenser 60 may be a 15.0 mfd. capacitor. The resistors SI and 62 have 20 megohms and" 1 5 megohms resistancerespectively. The resistors 64, 6.5 and 66 haveiresistances of 100,000 ohms, 5 'megohms and 7 .5 ,megohms respectively. The rectifier '61 is a low capacity selenium rectifier capable 'of handling up to 5 milli-amperes of current. The resistors '10 and. 14 have resistances of 60 .megoh ns and 100,000 ohmsrespectively. The photo tube 49 may be a IP39 type. The light source is about a 3 candle power incandescent'bulb drawing about lampere at 5 volts.

'While therehas been shownand described a preferred embodiment of the present invention, andthe; essential and non-essential features thereof have been 'set out in adequate detail to teach those skilled in the art the best manner of making and using :the device, some alternative constructions "have been described and others will suggest themselves from the foregoing description tothose skilled in the art, I ,do not wish to be limited, therefore, except by the scope of'the appended. claims, which areto be construed validly as broadly ,as the state of the prior art permits;

Whatfis claimed is: c

1. Apparatus adaptedfpr intermittent operation-for drying the hands of a user, comprising a support, fheat storage means comprising a body of material carried by said support and having a "substantial heat storage capacity; means forming an air passage through said apparatus from a downwardly directed inlet from the atmosphere located at a level below that of said body of material, passage means past said .body of material and 'in good heat transferring relation therewith to a downwardly directed outlet through which air may fiow toward anareawhere the hands of a user may be located to be dried, said outlet also being located at a level below that of said bo y of materiaLisaid air passage forming means being closed to the atmosphere except for said inlet and said outlet so as to prevent convection heat losses from said body of material; an air blower located in said air passage forming means, an electric motor for actuating said blower; an electric heating element mounted in good heat transferring relation to said body of material and having a heating capacity substantially less than that which would be required for heating air to a selected drying temperature at the rate at which air is moved by said blower, an electric circuit adapted for substantially continuously supplying energy to said heating element for thereby supplying heat to said heat storage means at a relatively slow rate, and means for intermittently actuating said blower for intermittently drying the hands of a user by air heated by withdrawing heat from said heat storage means at a relatively rapid rate during the intermittent periods of operation only of said blower.

2. Apparatus in accordance with claim 1, comprising in addition, a light source and a photocell respectively positioned on opposite sides of said area where the hands of a user may be located to be dried, and circuit means controlled by said photocell for controlling said air blower to cause the operation thereof whenever the hands of a user are in position in said area to interrupt the path of light between said light source and said hotocell.

3. Apparatus in accordance with claim 1, wherein said air blower is located in said passage means between said body of material and said downwardly directed outlet, so as to draw air past said body of material and to cause such air to flow through said outlet toward the hands of a user which are to be dried.

4. Apparatus in accordance with claim 1, wherein said electric heating element is bodily cast within said body of material, which is in turn of cast metal.

EDWARD D. SPIERER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,760,997 Shelton June 3, 1930 2,450,983 Osterheld Oct. 12, 1948 2,521,769 Arcularius Sept. 12, 1950 FOREIGN PATENTS Number Country Date 364,664 Great Britain Jan. 4, 1932 

